Compost is catching on

Bangor High School student Mike Mixon dumps waste into a compost bin in June. The composted soil is used to grow vegetables in the school's garden. With him are (from left) Tiffany Strout, Nick Dumond and Shane Rinks.

Michael York | BDN

Michael York | BDN

Bangor High School students Michael Mixon (left) and Shane Rinks show the results of what leftover scraps and hungry worms can produce to the tune of one ton per year in June. The composted soil is then used to grow vegetables in the school's garden.

Let’s talk garbage — how collecting and piling up decaying matter can make the world cleaner, your gardens healthier and your wallet fuller.

The compost industry in Maine has grown over the past 20 years from being virtually nonexistent to about 50 compost operations in the state, said Mark Hutchinson, University of Maine Cooperative Extension professor and part of the Maine Compost Team.

“When I talk to master gardeners, more than half are doing some sort of composting or recycling with organic materials,” said Hutchinson. “It’s definitely increased in popularity as people understand the value behind it.”

Removing organic materials from your trash and throwing them in a compost pile instead reduces the amount of trash you create and send to landfills. Many towns ask residents to pay per trash bag they dispose of, so in this case, what is ecologically conscious is also economically savvy.

Hutchinson gives about 60-70 compost talks a year at schools, museums, garden club meetings, businesses and colleges. His next talk will be a 50-minute presentation on methods for home composting at noon on Tuesday, Aug. 9, at the Merryspring Nature Center at 30 Conway Road in Camden.

Getting started is fairly painless and inexpensive.

Hutchinson’s favorite home compost pile is a circle or square built of lobster trap wire and posts. A 12-foot length of wire, at 3-4 feet in height, wrapped around the posts creates a perfect compost container that lets in the oxygen necessary for decomposition. Plus, the wire usually comes in multiple colors, such as green, black and yellow. Fasten solar lights on the posts. Decorate. Your pile doesn’t need to be an eyesore.

Even so, you might be thinking, “Sure, but that heated up mess is bound to stink.”

Since Hutchinson has experience throwing entire cows and the occasional whale into his compost piles, he seemed like the best person to ask about negating the odor of decaying matter.

His answer is to wrap it up in materials filled with carbon, a bio-filter, also known in the composting world as brown material: dead leaves, bark, peanut shells, sawdust, straw and, Hutchinson’s favorite, horse bedding.

Though heat is necessary for the speedy breakdown of organic products, composting can continue throughout the winter. In fact, in Maine, it’s almost necessary to continue composting throughout the long winter season to enrich gardens each spring with newly decayed material.

Hutchinson suggests collecting leaves in the fall and fluffing them up in the compost bin rather than packing them down. Then, throughout the winter, carry organic kitchen waste to the compost pile, lift up the lid — a good accessory to keep the snow out — and bury it under the leaves in different locations.

Nitrogen and carbon are responsible for breaking down compost, and equal portions of both are necessary. Nitrogen comes from green materials such as vegetable scraps, garden waste, grass clippings and manure. Carbon comes from brown materials: dead leaves, bark, fruit waste, newspaper, pine needles and sawdust.

“A lot of people talk about not putting meat and dairy products in your compost pile,” said Huntington. “Those things will all decompose, but if they aren’t well covered, they’ll attract dogs, cats, rats and mice.”

Put them in your pile with care and cover them with a carbon bio-filter.

The biggest compost pile no-no is using it as a repository for pet feces, which can carry diseases and resilient little pests such as roundworms and nematodes. The sweltering pile won’t kill them, and you’ll end up handling parasites and spreading them throughout your vegetable garden. Livestock feces, however, is safe.

The more often you turn the pile, the faster the process goes, but most home compost piles take eight to 18 months to break down, said Hutchinson.

Compost has a long list of benefits and, in the end, it’s perfect for replenishing your garden’s soil with nutrients and improving the soil’s water retention.

“I always tell people you need to feed your soil, not your plants,” said Hutchinson.

In addition to individual workshops, Hutchinson teaches a weeklong course twice a year with the Maine Compost Team at the Maine Compost School at Highmoor Farm in Monmouth. The Maine Compost Team is Mark King from the Maine Department of Environmental Protection, Bill Seekins from the Maine Department of Agriculture, George MacDonald from the Maine State Planning Office and Hutchinson.

For information about the composting course in Maine, visit composting.org or call 832-0343.

• If you add weeds to your pile, make sure the pile is hot or it will not kill the weeds. Instead, the weeds with grow and start stealing all the nutrients you’re trying retain.

Tips for compost pile building

• A good size for a pile is a 3 foot cube or slightly bigger. It’s a manageable size to turn and it’s ideal for retaining heat while allowing airflow.

• For faster decomposing, keep your bin in direct sunlight.

• Compost piles should remain damp but not too wet. As you build your compost pile, make sure that each layer is moist as it is added.

• To cut down on the anaerobic process, which creates strong odors, aerate the pile regularly, creating air spaces and limiting the anaerobic microbes while stimulating aerobic microbes, which smell less. Also, add elements to your pile that contain carbon.

• Compost can either by layered — thin layers of alternating green and brown material — or they can all be thrown together and mixed well.

• For faster results, use a compost turner every to weeks to aerate the pile.

• Collect your organic waste over a couple of days and add it in one big bunch. The more you add at one time, the most your compost will heat up.

• Do not compress your pile.

Tips for use

• Compost decomposes fastest between 120 and 160 degrees. Decomposition will occur at lower temperatures, but it takes much longer. When your compost is done, you should not be able to recognize any of the items you put in. It should be rich brown and about half the volume of the starting materials.

• Soak finished compost in water to make “compost tea,” a nutrient-rich liquid that can be used for watering plants in your garden or houseplants.

• Apply finished compost to your garden about 2-4 weeks before you plant, giving the compost time to integrate and stabilize within the soil.

Correction:An early version of this story incorrectly located Highmoor Farm. It is in Monmouth.